Quote from aquarian1:
They do not seem to be in line, either in direction or levels, far beyond the regular difference one would expect in index or metal futures.
Is the current disparity due to particularities of this season crops?
The disparity will vary from season to season. (see attached) So it's not just this season.
One can't compare the dissimilarity in the contract months in Corn to the general correlation one would see in the indices' or metals. The index and the metals deal with a more or less fixed product. Time, Fair value, market expectations, etc. No need to export the YM to China.
In different Corn contracts one may be dealing with Old crop vs. New Crop, World Supply and Demand, weather that can affect the planting, growing, and harvesting.
Today's DJ CBOT Corn Outlook is a good example:
CHICAGO (Dow Jones)-- U.S. corn futures are expected to open slightly lower Wednesday as a quick start to the planting season limits concern about this year's crop. Traders expect Chicago Board of Trade futures to open 1 to 3 cents lower. With U.S. corn planting already more-than-halfway done, widespread rains across the corn belt this week, which would typically be a source of anxiety at this time of year, are not a major concern. For those who have already planted, the rains, along with warm temperatures this week, are ideal for crop development, particularly in areas across the Midwest that have been relatively dry in recent months. Those who have yet to plant might miss out on the optimum planting dates, but still have plenty of time to get the crop in the ground without worrying about yield loss. Nearby corn supplies remain tight, which is why the May and July contracts are trading at a large premium to December. But the fast development of the new corn crop is producers confidence to start marketing their crops more aggressively, limiting the market's upside. The rapid planting pace has cooled off a market that soared last week on huge export sales, which most traders have assumed are to China. The U.S. Department of Agriculture reported more sales Wednesday, noting fresh export sales of 130,000 metric tons of corn for delivery to unknown destinations during the 2012/2013 marketing year.